Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming climate
Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming climate
复制标题
DOI：
10.1126/sciadv.aaz4876
复制
发表时间：
2020-06-01
期刊：
影响因子：
13.6
通讯作者：
Hu, Shineng
中科院分区：
文献类型：
--
作者：
Liu, Wei;Fedorov, Alexey, V;Hu, Shineng
虽然大西洋经向翻转环流（AMOC）预计将在人为变暖下减缓，但AMOC在未来气候变化中的确切作用尚未完全量化。在这里，我们提出了一种方法，以稳定的AMOC强度在人为变暖实验中，从亚极地北大西洋的淡水。这种方法使我们能够在全物理气候模式的实验中隔离AMOC气候影响。我们的研究结果表明，一个减弱的AMOC可以解释格陵兰岛南部的海洋冷却，类似于北大西洋变暖洞和减少北极海冰损失在所有季节的延迟约6年出现无冰北极在北方夏季。在对流层，减弱的AMOC导致一条从高纬低层向热带高层伸展的异常冷却带，并使北方半球中纬急流向极地移动。
While the Atlantic Meridional Overturning Circulation (AMOC) is projected to slow down under anthropogenic warming, the exact role of the AMOC in future climate change has not been fully quantified. Here, we present a method to stabilize the AMOC intensity in anthropogenic warming experiments by removing fresh water from the subpolar North Atlantic. This method enables us to isolate the AMOC climatic impacts in experiments with a full-physics climate model. Our results show that a weakened AMOC can explain ocean cooling south of Greenland that resembles the North Atlantic warming hole and a reduced Arctic sea ice loss in all seasons with a delay of about 6 years in the emergence of an ice-free Arctic in boreal summer. In the troposphere, a weakened AMOC causes an anomalous cooling band stretching from the lower levels in high latitudes to the upper levels in the tropics and displaces the Northern Hemisphere midlatitude jets poleward.